1. Technical Field
The present disclosure relates to an etching apparatus. More particularly, the present disclosure relates to an etching apparatus for substrates using an etching solution.
2. Description of the Related Art
Typically, a flat display device includes one of the following devices such as, for example, a liquid crystal display (LCD), a plasma display panel (PDP), or an organic light emitting diode (OLED). The flat display device is used for various display devices, such as, for example, a large-sized television (TV), a monitor of a lap-top computer, and a mobile phone.
A flat display device is provided with substrates. For example, in an LCD using liquid crystals, two transparent glass substrates are disposed opposite to each other and the liquid crystals are interposed therebetween. Moreover, due to the recent trend of making the flat display device lighter in weight and thinner in size, studies have been conducted for developing a thin flat display device. For example, these studies have been aimed at producing a thin flat display device, by for example, reducing the thickness of the substrate of these devices. In this regard, to reduce the thickness of the substrate an etching technique for the substrate has been developed. According to this etching technique, the substrate is etched using an etching solution, thereby reducing the thickness of the substrate.
However, one using the above-mentioned conventional etching technique may encounter the following difficulties set forth below:
First, the substrate may not be uniformly etched, which may in turn result in the display device having defects in image quality during the operation of the display device.
Second when a certain region of the substrate is excessively etched, the corresponding region of the substrate may become thin, and thus the substrate may become damaged during the etching process. For example, when a plurality of substrates are etched at the same time, if any one of the substrates is damaged, debris from the damaged substrate may cause the neighboring substrates to be damaged as well.